Testing and inspection

In wafer test, what is it called to push the probe needles slightly further after they touch the bond pads to ensure contact?

  1. AUnderfill
  2. BGuard band
  3. COverdrive
Show answer and explanation

Answer: C. Overdrive

Pushing the probe needles a further few tens of µm beyond the point where they touch the pad is called overdrive. The needle tips break through the oxide on the pad surface, giving stable electrical contact. Pushing too far may damage the pad and the structures beneath it.

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More Testing and inspection questions

  1. Which pair correctly names the two properties that design for testability aims to improve?
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